#include <iostream>
#include <queue>
#include <list>
using namespace std;

int main() {
    queue<int, list<int>> q;
    q.push(1);
    q.push(2);
    q.push(3);
    q.push(4);
    q.push(5);
    q.push(6);
    cout << q.size() << endl;
    while(!q.empty()) {
        cout << q.front() << endl;
        q.pop();
    }
    return 0;
}